Which of the following orders is not correct for the given property?

Which of the following orders is $CORRECT$?

Given below are two statements:
Statement-$I$: The correct order in terms of atomic/ionic radii is $Al > Mg > Mg^{2+} > Al^{3+}$.
Statement-$II$: The correct order in terms of the magnitude of electron gain enthalpy is $Cl > Br > S > O$.
In the light of the above statements, choose the correct answer from the options given below:

Select the correct statements from the following:
$(a)$ Effective nuclear charge for nitrogen is $3.90$
$(b)$ $IP$ of $Ne$ is more than $Na^{+}$
$(c)$ Order of electronegativity $sp > sp^2 > sp^3$
$(d)$ Order of acidic character $NH_3 < PH_3 < AsH_3$

Consider the following elements $In$,$Tl$,$Al$,$Pb$,$Sn$ and $Ge$. The most stable oxidation states of elements with highest and lowest first ionisation enthalpies,respectively,are

An element of atomic weight $40$ has $2, 8, 8, 2$ as the electronic configuration. Which one of the following statements regarding this element is not correct?